Effect of support modification on the characterization and catalytic activity of Mo/Al2O3 catalysts

Molybdenum catalysts (15 wt% MoO3 loading) supported on alumina, alumina–magnesia, and alumina–chromia were prepared via impregnation technique and studied for the reaction of methyl-cyclohexane dehydrogenation. The catalysts were evaluated by means of FT-IR, XRD, DSC, TPR, and N2 adsorption–desorption isotherms. The results clarified that Mo/alumina–magnesia catalyst possesses small crystallite size and high surface area (240 m2/g) and is selective toward the formation of dehydrogenated product (96.5%). The yield to ring-opening products is higher on Mo/alumina–chromia catalyst due to its higher acidity and larger metal crystals, which favor the ring-opening reaction and lower metallic activity with selectivity toward ring-opening products (32%).

Graphical abstractMo supported on alumina, alumina–magnesia, and alumina–chromia catalysts were prepared via impregnation method and studied for dehydrogenation reaction of methyl-cyclohexane. Mo/alumina–magnesia catalyst is characterized by small crystallite size, high surface area, high activity, and selectivity for dehydrogenation reaction. Mo/alumina–chromia favored agglomeration, low surface area, and high activity and selectivity toward ring-opening products.Figure optionsDownload full-size imageDownload as PowerPoint slide